Police took the unusual step of naming Jallow as a suspect and releasing CCTV images of him on a bus in Newington Causeway near Elephant & Castle.

"We welcome the sentence that has been handed down today; this was an appalling and violent attack on a promising A-level student who was simply seeking the return of his brother's mobile phone," said Detective Chief Inspector Matt Bonner.

"Dogan paid the ultimate price for daring to face up to the thieves, while his brother had to endure the tragedy of watching him die in front of his eyes. One can scarcely imagine the heartbreak suffered by Dogan's family.

"Jallow did all he could to evade capture in the weeks following the attack, until he realised there was nowhere left to run. He will now spend a significant amount of time behind bars for the callous crime that he has committed."